Plans for a development of 13 residential flats and two commercial units are being vigorously opposed by Lewes residents.
Vehicle dealership Caffyns has applied to convert offices at the old Culverwell site off Davey’s Lane.
But people living in one of the county town’s smallest roads have launched a ‘Save Our Street’ campaign.
They say tiny Thomas Street would be the access road to the proposed development – with serious road safety implications.
They claim local people have not been properly consulted on the application, which is now before the South Downs National Park Authority. Comments must be received by November 28.
Campaigners are trying to persuade Caffyns that there are alternative and more appropriate access roads, which would not impact on Thomas Street or the wider Malling community.
Phil Wilkinson said: “I think no thought has been given to the residents and the huge impact the access to the proposed site will have on families. Plans to turn Thomas Street into a two-way access to the proposed site are wholly unrealistic.
“A quiet residential community street will soon become a congested driveway.
“We have watched the industrial roads behind the houses become busier with erratically driven commercial vehicles that are hazardous to children and adults alike.
“Unrealistically shoehorning some hastily planned pipedream may look great on paper but in the everyday lives of people who live nearby it will be nothing but thoughtless and inconsiderate planning, with profits taking place over people.”
East Sussex County Council Highways has recommended that the application be refused.
Suzanne Rose said: “I wholeheartedly object to the proposals for the re-development of the Culverwells site, in particular the use of Thomas Steet as an access road.”
She said she would welcome a proposal to restore the Listed building to its former glory and make provision for residential flats but “this proposal in its current guise is unacceptable”.
She said that Thomas Street, which dates from the 1830s, was so narrow that cars drive on the pavement past the resident parking bays yet this application suggested that a two-way flow of traffic would be feasible.
Caffyns had boarded up the end of the street in February, she added, effectively forcing residents to reverse their cars onto busy Malling Street, a dangerous and illegal manoeuvre.
The three-storey Culverwell building dates from 1836 and is Grade II Listed. It was built in the neo-classical style. Particularly imposing are the windows on the first and second floors which are in double-storey arched recesses.
It was the production and bottling centre for the former Southdown Brewery, which served numerous pubs in Lewes and the surrounding area until it closed in the 1920s.
It is understood that Thomas Street, originally two cottages longer, was built to house the brewery workers.